Fig. 4

Non-diffraction range and effective current vs. beam width. The plot shows the non-diffraction range (blue curves) and effective current (red curves) vs. beam width, for our non-diffracting wavefunctions (solid curves), for multi-electron Bessel (dashed curves) and Gaussian (dotted curve) EBeams with zero OAM. The effective width of our non-diffracting multi-electron beam is bounded from above at the blue dot, where the main lobe is over-wide, carrying the upper limit on the current. This upper limit occurs because the interference of our shaped wavepacket can balance the beam self-repulsion and diffraction only up to a certain value, above which the beam spread is too strong for the predesigned interference effects (arising from the structure of the beam) to compensate for it. For beams of effective width much narrower than the critical width (marked by the dashed vertical line at 4.2 nm) our non-diffracting multi-electron wavefunction coincides with the Bessel function. This critical width decreases as the current is increased and can go below 1 nm. Here, the EBeams are accelerated by voltage of 200 V, having beam current of I = 5 μA